1. Field of the Invention
The present invention relates to toilet mechanisms, and particularly to a water conservation device to conserve water in the toilet tank.
2. Description of Related Arts
The present invention relates to a toilet tank system which has a flapper valve between the toilet tank and the toilet bowl. In a conventional system, when the handle is operated to flush the toilet, the flapper valve is pulled off the flush valve seat. The water in the tank flows through the tank outlet into the bowl or into the leg of a trap of the bowl, causing the water to empty rapidly from the tank and flush the bowl through a siphoning action. When the handle is released, the flapper valve floats in the tank water until substantially all of the water is released from the tank, after which it seals the valve seat. The tank then refills with water until a float in the tank rises with the water level to close the float valve in the ballcock assembly, leaving a premeasured quantity of water in the tank until the next flush cycle.
In recent years concern for water shortages has led to the observation that the quantity of water released from the toilet tank exceeds the volume necessary for adequately flushing the toilet bowl by anywhere between 30% and 50%. In response to this observation, a number of devices have been contrived for the purpose of limiting the amount of water released from the water tank during a flush cycle. Limiting the amount of water released from the water tank during the flush cycle also has the secondary effect of reducing the risk of water overflowing the tank bowl in the event of a clogged toilet.
U.S. Pat. No. 4,937,895, issued Jul. 3, 1990 to C. F. Stevens, discloses an upright tube slidably disposed about the overflow tube, the upright tube having a valve actuator mounted above the flapper valve in order to press the valve down on the valve seat, and also having a float causing the upright tube and valve actuator to rise and fall with the water level, the float partially filling with water to counteract its buoyancy. U.S. Pat. No. 5,023,960, issued Jun. 18, 1991 to S. Ratanagsu, teaches a device having an L-shaped support block clamped to the overflow tube, a support rod depending from the block, a float member with an upper chamber filled with water and a lower chamber filled with air attached to the rod, and an adjustable sleeve threaded on the bottom of the support bar, the sleeve pressing the flapper valve down on the valve seat.
U.S. Pat. No. 5,103,507, issued Apr. 14, 1992 to Sprajc, et al., shows a device adapted for both flapper and ball valves, having a spring clamp with a pair of horizontal guides attached lo the overflow tube, a U-shaped thrust member for pressing the valve onto the valve seat, the U-shaped member having a pair of vertical arms at the ends of the U with floats mounted on weights circumferentially around the vertical arms which extend through the horizontal guides, and adjustment clips on the vertical arms between the floats and the guides. U.S. Pat. No. 5,185,891, issued Feb. 16, 1993 to L. Rise, describes a device for converting the flapper valve to manual operation in the form of a forked stop disposed on the overflow tube above the flapper valve.
U.S. Pat. No. 5,191,661, issued Mar. 9, 1993 to F. C. Chang, teaches a device which includes a block mounted on the overflow tube, a hanger mounted on the block with a pawl pivotally mounted on the hanger, a float with an extension having protrusions, a pusher with holes which mate with the protrusions on the float extension, and a lever having two chains, one connected to the flapper valve and the other connected to the pawl. U.S. Pat. No. 5,333,331, issued Aug. 2, 1994 to J. R. Battle, shows a hemispherical flush regulator pivotally mounted to the overflow tube above the flapper valve, optionally having a second pivot at the junction of the pivot arm and the flush regulator, which operates in partial flush and full flush modes.
U.S. Pat. No. 5,341,522, issued Aug. 30, 1994 to J. Munro, describes a water conservation device having an elongate cylinder hanging from a side wall of the tank, one end of which is attached to the flapper valve in order to pull the valve closed by the weight of the cylinder. U.S. Pat. No. 5,375,269, issued Dec. 27, 1994 to P. J. Schmitz, discloses a water saving device with a float having an upper cup and a lower cup slidable on the overflow tube, the lower cup having a tongue with dimples which engage holes or depressions on the upper cup in detent fashion to adjust the travel of the float, the float pressing the flapper valve closed on the valve seat.
U.S. Pat. No. 5,548,849, issued Aug. 27, 1996 to A. M. Sulit, shows a flexible line hung from one side of the tank, one end of the line tied to the flapper valve and the other end of the line tied to the float, so that as the float goes down with the drop in water level, the flapper valve is pulled closed on the valve seat. U.S. Pat. No. 5,784,726, issued Jul. 28, 1998 to S. G. Kay, describes a spherical rubber ball with a bore through a diameter of the sphere which slides over the overflow tube in order to limit the upward travel of the flapper valve.
None of the above inventions and patents, taken either singly or in combination, is seen to describe the instant invention as claimed.